integration: use constants for http methods
integration: use constants for http methods

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

konstruktoid/docker-upstream,ibuildthecloud/docker,Ramzec/docker,AkihiroSuda/docker,trebonian/docker,AkihiroSuda/docker,jimjag/docker,gnailuy/docker,kojiromike/docker,bearstech/moby,cpuguy83/docker,AkihiroSuda/docker,bearstech/moby,paralin/docker,justincormack/docker,konstruktoid/docker-1,estesp/docker,jvanz/docker,ibuildthecloud/docker,Ramzec/docker,docker/docker,thaJeztah/docker,justincormack/docker,paralin/docker,vdemeester/docker,jthelin/docker,djs55/docker,yongtang/docker,nalind/docker,flavio/docker,paralin/docker,nawawi/docker,Ramzec/docker,flavio/docker,docker/docker,docker/docker,konstruktoid/docker-upstream,nawawi/docker,jimjag/docker,moby/moby,djs55/docker,moul/docker,nawawi/docker,jimjag/docker,moul/docker,trebonian/docker,jimjag/docker,cpuguy83/docker,nalind/docker,flavio/docker,konstruktoid/docker-1,thaJeztah/docker,mahak/docker,thaJeztah/docker,cpuguy83/docker,moby/moby,djs55/docker,vdemeester/docker,mahak/docker,gnailuy/docker,SvenDowideit/docker,estesp/docker,gnailuy/docker,pradipd/moby,dims/docker,ibuildthecloud/docker,jameszhan/docker,jvanz/docker,bearstech/moby,Mokolea/docker,yongtang/docker,moul/docker,ibuildthecloud/docker,mahak/docker,Mokolea/docker,pradipd/moby,kojiromike/docker,yosifkit/docker,moul/docker,nalind/docker,konstruktoid/docker-upstream,Mokolea/docker,jameszhan/docker,flavio/docker,dims/docker,justincormack/docker,jameszhan/docker,SvenDowideit/docker,paralin/docker,AkihiroSuda/docker,trebonian/docker,jthelin/docker,estesp/docker,thaJeztah/docker,kojiromike/docker,pradipd/moby,nalind/docker,ibuildthecloud/docker,moby/moby,gnailuy/docker,dims/docker,Ramzec/docker,mahak/docker,SvenDowideit/docker,yosifkit/docker,cpuguy83/docker,jvanz/docker,konstruktoid/docker-1,yosifkit/docker,Mokolea/docker,yongtang/docker,bearstech/moby,trebonian/docker,moby/moby,nawawi/docker,konstruktoid/docker-upstream,vdemeester/docker,yosifkit/docker